1. Field of the Invention
The present invention relates to a print simulation apparatus for simulating a color printed image on a screen of a color monitor in order to adjust and check color separation conditions (various color correction amounts) when a color original is printed in color and, more particularly, to a print simulation apparatus which is used in combination with a conventional color scanner and is convenient for proofing.
2. Description of the Related Art
When a color print is made, a color original is scanned by a color scanner, and various color corrections are made on the picked-up image signal. Thereafter, the corrected image signal is color-separated, and color separation plates are formed in accordance with color separation signals. A proof plate is formed by combining the obtained color separation plates, characters, and a plane mesh in accordance with a layout, and is set in a proof press to perform proofing. The color separation conditions (various color correction amounts) are checked based on color tone of the obtained proof. If the color tone of the proof is not achieved, the color correction amounts are changed and color separation is performed again. Thereafter, formation of color separation plates and proofing are performed again. When a proof having preferable color tone is obtained, a press plate is formed based on the corresponding color separation plates, and is set in a printing press.
Such proofing requires much time, cost and labor. Therefore, in recent years, various print simulation apparatus using color monitors have been developed. With these apparatus, the finished state of a print can be simulated on a color monitor and color separation conditions can be checked without proofing.
A conventional print simulation apparatus comprises a memory for temporarily storing an image signal derived from a color scanner, and a color correction circuit, having the same arrangement as that arranged in the color scanner, for color-correcting a signal read out from the memory. The output from the color correction circuit is supplied to the color monitor, and the finished state of a print is simulated on the color monitor. Thus, color separation conditions can be electronically checked, and the color correction circuit of the print simulation apparatus is adjusted, so that preferable color correction amounts, i.e., color separation conditions can be determined.
However, in a print simulation apparatus of this type, during simulation for determining changing color separation conditions, not an operation section (dials, knobs, and the like) of a color correction apparatus of the color scanner, but the operation section of the color correction circuit of the print simulation apparatus, is adjusted. For this reason, when color separation plates are formed after simulation, parameters of the operation section must be set again according to that of the color correction circuit of the color scanner, resulting in cumbersome operation for an operator. If the operation section is of analog type, identical values cannot often be precisely set.
Moreover, in the conventional simulation apparatus, a simulated image of one color original is merely displayed on a monitor screen, and an overall comparison with a simulated image of another color original or a partial comparison of identical color tone portions of another color original cannot be performed. For this reason, when a plurality of color originals are printed in one print, the overall color tone and gradation cannot be matched. As a result, the color tone and gradation of a print as a whole cannot be matched.
Finally, in the conventional print simulation apparatus, a print simulated image is merely displayed on a color monitor. Thus, a setting value or location of a highlight set level associated with white balance cannot be specified.